Extending wireless router's range

[uhrams]

Commercially available wireless routers for home and office networking have a very poor range and often the signal strength is not sufficient across rooms with closed doors/walls. The transmitter power/antenna gain needs a boost for extending the range or some kind of wi-fi repeaters are needed. The range should be atleast a 100 meters and should work across closed doors/walls and across floors as well and the USB wi-fi adapter should be functional.

Any solutions ?

 

[hameeds01]